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3 years ago

A sample of lithium sulfate, (Li2SO4), has 2.94 x 1023 atoms

Chemistry

1 answer:

Crazy boy [7]3 years ago

3 0

Answer:

0.245 moles

Explanation:

moles of lithium = 2*moles of Li2SO4

so moles of LI2SO4=2.94*10^23/(2*6*10^23)=0.245

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Describe the pattern of temperature changes within the layers of the atmosphere. Why do you think temperature changes follow thi

ser-zykov [4K]

Answer:

The atmosphere refers to the gaseous envelope of earth, comprised of variable gases with definite proportions. The layers of the earth's atmosphere are as follows-

Troposphere- This layer starts from the ground and extends up to a height of about 10 km. Here, the temperature decreases with the increasing altitude. All the weather phenomenon takes place in this layer.

Stratosphere- It starts from 10 km and extends up to a height of about 50 km. Here the temperature increases as the altitude increase. This is because of the presence of the ozone layer that receives the harmful UV radiation emitted from the sun.

Mesosphere- This layer extends from a height of about 50 km to about 80 km above the earth's surface. Here, again the temperature decreases with the increasing altitude.

Thermosphere- This layer starts from a height of about 80 km and extends up to about 500 km above the ground surface. In this region again the temperature increases with the increasing elevation.

Exosphere- This layer ranges from about 500 km to 10,000 km above the earth's surface. Here, the temperature gradually increases with the increasing height.

This variation in temperature occurs because of the certain reason. In the troposphere and the mesosphere, the temperature decreases with height because the pressure and height are inversely proportional to each other. The stratosphere experiences increasing temperature because of the presence of the ozone layer that is responsible for holding the greenhouse gases and the harmful UV radiation. The thermosphere and the exosphere experience high temperatures because of the receiving of the direct sunlight. Due to these above reason, there occurs this temperature change in a unique pattern.

6 0

3 years ago

A solution is prepared by dissolving ammonium sulfate in enough water to make of stock solution. A sample of this stock solution

Pani-rosa [81]

Answer: molarity of ammonium ions = 0.274mol/L

molarity of sulfate ions = 0.137mol/L

Note: The complete question is given below

A solution is prepared by dissolving 10.8 g ammonium sulfate in enough water to make 100.0 mL of stock solution. A 10.00-mL sample of this stock solution is added to 50.00 mL of water. Calculate the concentration of ammonium ions and sulfate ions in the final solution.

Explanation:

Molar concentration = no of moles/volume in liters

no of moles = mass/molar mass

mass of ammonium sulfate = 10.8g, molar mass of ammonium sulfate, (NH₄)₂SO₄ = (14+4)*2 + 32+ (16)*4 = 132g/mol

no of moles = 10.8g/132g/mol = 0.0820moles

Molarity of stock solution = 0.0820mol/(100ml/1000ml* 1L) = 0.0820mol/0.1L Molarity of stock solution = 0.820mol/L

Concentration of final solution is obtained from the dilution formula,

C1V1 = C2V2

C1 = 0.820M, V1 = 10mL, C2 = ?, V2 = 60mL

C2 = C1V1/V2

C2 = 0.820*10/60 = 0.137mol/L

molar concentration of ions = molarity of solution * no of ions

molarity of ammonium ions = 0.137mol/L * 2 = 0.274mol/L

molarity of sulfate ions = 0.137 mol/L * 1 = 0.137mol/L

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3 years ago

When interviewed, Mr. Harrison was discussing barometric pressure and the low-pressure system moving in that may cause a change

Zarrin [17]

A meteorologist?? I could be totally wrong though! :)

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anygoal [31]

B. 51 50
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RoseWind [281]

C. a symmetrical molecule is always nonpolar

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